The invention relates to roofing tools and, more particularly, to a tool for laying out boards for building rafters.
To lay out rafters for constructing a roof involves measuring and cutting boards for common rafters, valley rafters, hip rafters and jack rafters. Each rafter must be cut to the proper length with the correct angles and seat cut.
There are several kinds of tools which may be used to lay out rafters. One such device is a speed square which includes graduated markings for determining angles and lengths. The speed square is currently used in combination with a tape measure.
A rafter tool is disclosed in U.S. Pat. No. 2,744,332 entitled xe2x80x9cRafter Toolxe2x80x9d. The tool includes a main body having horizontal and vertical arms and a flexible rule. The tool is positioned on a plate member of a building and the flexible rule is pulled to the peak of the building. An aligning arm is clamped in position to defme the rafter angle. The tool is then moved to a board and the clamped aligning arm is laid on the board to transfer the size of the angle onto the board. However, the tool does not include graduated markings for noting the degree of the angle when the tool is positioned on the building and the tape rule is cumbersome and difficult to maneuver.
U.S. Pat. No. 4,462,166 entitled xe2x80x9cDevice for Measuring Lengths and Conforming Anglesxe2x80x9d discloses a tool having telescoping members to measure the distance between the peak of the building and the wall of the building. However, the telescoping members are cumbersome and difficult for one person to maneuver.
Therefore, what is needed is an apparatus and method for laying out rafters which utilizes at least one support bracket in combination with a lightweight, flexible extension member for providing a length and at least one angle for the roof rafter.
A rafter tool for use with a speed square having graduated markings includes a first support bracket attached to the speed square and positioned on a lower portion of the building. An extension member is extendable between the lower portion of the building and an upper portion of the building for providing a distance between the upper portion of the building and the lower portion of the building. The extension member is alignable with the graduated markings of the speed square for providing an angular measurement for a rafter board.
Additionally, the rafter tool may further include a second support bracket positioned on an upper portion of a building. The extension member extends between the first support bracket and the second support bracket.
The rafter tool further includes a guide member attached to the first support bracket and slidable along the rafter board for providing a pivot point for the rafter tool when laying out the rafter board.
A method for laying out rafters includes the steps of attaching a speed square to a first support bracket, positioning the first support bracket having a speed square attached thereto on a lower portion the building, and extending a string from the first support bracket to an upper portion of the building. After an angle on the speed square which aligns with the string is read, the first support bracket and the string is removed from the building.
The string from the upper portion of the building is positioned on one edge of the board and the first support bracket with an opposite end of the sting attached thereto is laid on the board. A guide member of the first support bracket is slid along the board until the string is pulled tight and the string is aligned with the angle read on the speed square by pivoting the first support bracket about the guide member for positioning the first support bracket on the board.
The board is marked along an edge of the speed square for laying out a first cut on the board and the board is marked along the first support bracket for laying out a second cut on the board for providing a seat cut to fit the board to the lower portion of the building.
The method may further include the steps of attaching the string to a second support bracket, which is positioned on the upper portion of the building for extending the string between the first and second support brackets. The method may further include marking an opposite end of the board along the speed square for laying out a third cut on the board for fitting the board to the upper portion of the building.